1. Field of the Invention
This invention generally relates to an electronic lock having a manual override which can be manually actuated in the event of a failure of the associated electronics. More particularly, the present invention relates to an electronic lock having an electronically controlled stopper which is actuated by a first electronic key to electronically remove the stopper from engagement with a latch assembly. Continued movement of the first key moves the latch to open the lock. The lock can also be actuated by a second manual key assembly which includes a cam that drives a cam follower interconnected with the stopper to manually remove the stopper from engagement with the latch assembly. Continued movement of the second key moves the latch assembly to open the lock to allow for manual actuation of the latch assembly to manually open the electronic lock.
2. Related Art
Security locks are necessary and widely used for public telephones, vending machines and other devices which are the subject of thefts and/or targets for vandals. Because the coin banks within such devices hold relatively large amounts of money, the devices become attractive targets. Additionally, these devices are often times located in remote areas which increases the likelihood that the devices will become targets. Further, often times there is valuable electronic equipment contained within such devices which even further increases the likelihood that such devices will become targets for theft.
Additionally, it is common that the keys to such devices are provided to service men or money collectors to allow them access to the interior of the housing to either service the machine or collect money that has been deposited in the machine. In order to provide security, it is desirable to utilize an electronic lock, i.e., a lock having a stopper that coacts with a latch assembly that prevents movement of the latch and operation of the lock unless and until the stopper is withdrawn from engagement with the latch assembly. The stopper is typically moved by a solenoid switch which is electronically actuated. A major advantage of using an electronic lock, apart from security, is that access to the housing can be monitored and then checked. In this way, one can be prevented from visiting a device more than once in a day. The data that the electronic lock assembly acquires can be used to track the usage thereof.
However, one problem that exists with electronic locks is that if for some reason the electronics fail, there is no suitable way of actuating the lock to access the housing. Accordingly, in cases where the electronics fail, often times the lock must be destroyed in order to gain access to the housing. This results in expensive property damage and the lock must be replaced. Even the housing can be damaged in such instances.
Accordingly, what is desired and has not heretofore been developed is an electronic lock which is electronically actuated by a first key, but which can also be manually actuated by a second key to withdraw a stopper from engagement with a latch to allow the lock to be actuated in the event of an electronics failure, and/or to allow one to manually override the electronic controls associated with an electronic lock.